CollectionBase.OnInsert Method (Int32, Object)
Performs additional custom processes before inserting a new element into the CollectionBase instance.
Assembly: mscorlib (in mscorlib.dll)
abstract OnInsert : index:int * value:Object -> unit override OnInsert : index:int * value:Object -> unit
Parameters
- index
-
Type:
System.Int32
The zero-based index at which to insert value.
- value
-
Type:
System.Object
The new value of the element at index.
The default implementation of this method is intended to be overridden by a derived class to perform some action before the specified element is inserted.
The On* methods are invoked only on the instance returned by the List property, but not on the instance returned by the InnerList property.
If the process fails, the collection reverts back to its previous state.
The default implementation of this method is an O(1) operation.
Notes to Implementers:
This method allows implementers to define processes that must be performed before inserting the element into the underlying System.Collections.ArrayList. By defining this method, implementers can add functionality to inherited methods without having to override all other methods.
OnInsert is invoked before the standard Insert behavior, whereas OnInsertComplete is invoked after the standard Insert behavior.
For example, implementers can restrict which types of objects can be inserted into the System.Collections.ArrayList.
OnValidate is called prior to this method.
Available since 10
.NET Framework
Available since 1.1